Aux Sends Explained: Monitor Mixes and Effects Routing

Auxiliary sends create independent signal paths from the main mix, enabling monitor mixes, effects routing, and other secondary outputs. Understanding aux sends unlocks essential mixing capabilities that separate basic reinforcement from professional sound.

What Aux Sends Do

Aux sends tap signal from each channel, creating copies routed to separate outputs. The main signal continues to the main mix unaffected; the aux send creates an independent path.

Each aux bus collects contributions from every channel’s aux send control. The aux master controls the overall level of that combined bus before it reaches its output.

Multiple aux buses (4, 6, 8, or more depending on the mixer) enable multiple independent mixes. Each can serve a different purpose: monitor mix 1, monitor mix 2, reverb send, delay send, and so on.

Pre-Fader vs Post-Fader

Pre-fader sends tap the signal before the channel fader. The aux send level remains constant regardless of fader position. Moving the fader does not affect the aux send.

Post-fader sends tap the signal after the fader. When the fader changes, the aux send level changes proportionally. Lowering the fader reduces the aux send.

Monitor sends typically use pre-fader. The performer’s monitor level stays consistent even when the FOH engineer adjusts faders during the mix.

Effects sends typically use post-fader. When a channel fades out, its contribution to reverb or delay fades with it. The effect amount tracks with the dry signal.

Creating Monitor Mixes

Each monitor position can receive its own aux bus. Aux 1 to the lead vocal wedge, Aux 2 to the guitarist’s wedge, Aux 3 to the drum fill, and so on.

Building a monitor mix involves adjusting per-channel send levels for that aux bus. The drummer’s mix (Aux 3) might have high kick, snare, and bass sends with moderate vocal and guitar sends.

The aux master controls overall level going to that monitor. Channel sends control the balance within the mix; the master controls how loud the total mix is.

Creating effective monitor mixes requires understanding what each performer needs. Vocalists need themselves prominently; drummers need rhythmic reference; guitarists need vocal cues.

Effects Send Configuration

Effects processors receive signal through aux sends rather than being inserted directly on channels. This parallel configuration keeps the dry signal intact while adding processed signal.

Aux 5 might feed a reverb processor. Each channel’s Aux 5 send determines how much of that channel goes to the reverb. The reverb output returns through a dedicated return channel or a mixer input.

Multiple effects can use multiple aux buses. Aux 5 for reverb, Aux 6 for delay—each effect receives independent sends from each channel.

The dry/wet balance comes from the relative levels of original channel versus effect return. More effect return level means wetter sound.

Send Level Management

Start with sends at minimum and build up. Adding too much to aux sends creates feedback-prone monitors or overly wet effects.

The aux send control determines how much of each channel contributes to each mix. A channel can send different amounts to different aux buses simultaneously.

Unity on aux sends means the signal level matches the channel level. Boosting beyond unity increases level; reducing below unity decreases it.

The aux master provides overall control for the entire bus. Reducing the master reduces all contributions proportionally without affecting relative balance.

On vs Off vs Variable

Some consoles provide on/off switches for aux sends along with level controls. On/off makes the send active or inactive; level sets how much when active.

Other consoles have only variable controls—minimum level equals off. This approach works but requires precise positioning for true off.

Global mute for aux buses silences all sends to that bus. Useful for eliminating an entire monitor or effect output quickly.

Monitor-Specific Considerations

Each performer’s monitor mix represents their personal monitoring environment. Asking what they want and adjusting accordingly creates effective mixes.

Too much in monitors causes feedback and stage volume problems. Starting minimal and adding only what’s requested controls levels.

Consistent monitoring helps performers feel comfortable. Changes between songs should be subtle unless problems require correction.

Effects-Specific Considerations

Post-fader configuration ensures effects track with the mix. When the guitar solo ends and fader drops, guitar reverb fades too.

Effect return levels compete with dry signal. Too much return drowns the dry; too little makes effects inaudible.

Multiple effect sends from one channel can create complex processing. The vocal might send to both reverb and delay, each at different levels.

Troubleshooting Aux Send Issues

No signal to monitor: Check aux send level on relevant channels, aux master level, and physical connection to the monitor.

Too much feedback from monitors: Reduce aux send levels, check which channels contribute most feedback, apply EQ to the aux output.

Effects not heard: Verify aux send levels, check effect return routing, confirm effect unit is receiving and outputting signal.

Wrong sources in a mix: Review which channels have sends to that aux bus. Zero unintended sends.

Advanced Aux Applications

Matrix outputs on some consoles combine main and aux outputs in various configurations. Matrices enable zone feeds, broadcast outputs, and other complex routing.

Aux-fed subgroups route aux outputs to subgroup inputs, enabling group processing of monitor mixes.

External processing inserted on aux outputs can treat entire monitor mixes or effect sends globally.